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Yes!

Some are filling, but others not all the way. Then, I find out once I start sealing with shellac, and the pores won't fill. I hate it when more coats are brushed or sprayed or wiped on, and nothing will go down in those stupid tiny pits...

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

It takes a mighty long time to fill pores by brushing, spraying or padding on Shellac alone. If you have half filled pores you would be better served by delaying the actual finishing and going back to the pumice.
I don't know the Zinser seal coat but here's a few pointers when using the pumice method with straight shellac.
Put on two or three thin coats of Shellac (drying time between), a 1 ib cut. Allow the last coat to dry and sink, overnight - if not longer, before starting with the pumice. Applying pumice before the Shellac has dried/hardened has a tendency to create sticky mud. You end up pushing it in the pores and then dragging it out.
Try raking light and get low enough to see what is happening. I find it much quicker to do a small area and move on. I don't dwell on one area too long. Pointless trying to get a complete fill in the same area when it's still relatively soft. Go back to it when it's had time to dry and sink. Overall it takes longer but the actual working time is less. I fill pores quicker when I don't feel the need to fill pores quick - if you get my meaning! Use a fresh surface to the pad if you need to, especially If you are finding that it's clogging up and getting a little sticky. A fresh surface helps to mop up some of the excess shellac/pumice filler. If you want an absolute flat surface (years down the line) you will need to let it harden and sink over 4 or 5 days. Then repeat. Shellac takes a long time before it gets truly hard.

Michael (et. al.), thanks for the advice. May I ask a few questions?

I have pumice and shellac, but I would have to say that I am not familiar with the proper method of using the two together to fill pores. I've found myself with white pumice building up in pores, and the look is unpleasant to say the least! I was sprinkling pumice powder on the wood, and then using a fad loaded with shellac and added alcohol (everclear). I also tried applying the pumice directly to the pad/fad and adding shellac, which seemed better. For all I know, you are supposed to mix a bunch of the two in a jar or something.

(1) So what is the best method for this?

(2) I know this is probably a dumb question, but do you use any oil in this process, or just when laying on the build coats?

(3) Do you or does anyone else out there know if varnish can be padded on in a french polish technique? The Epifanes is a gorgeous looking finish also, and has the advantage of being phenolic based and very tough against body chemistry etc. And it is also a gorgeous finish. I was thinking of using FP to build most of the finish, then adding a few thin coats of varnish over the top for more durability and that warm look that I like...

Lastly, do you typically dry or wet sand between seal coats and build coats? I've been dry sanding between sealer coats (applying with pad in a swirling pattern) but get pretty tired of cleaning build-up off the sandpaper.

Thanks,

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I was curious if Royal Lac is similar to U-Beaut, I just did my first French polish on a guitar I made for my brother following Steve from VA's process. I filled with Aquacoat, and used a 1:1 cut of U-Beaut and Everclear for the whole process. I put on 40-50 sessions on the guitar per Steve's method, did the neck in true oil except for the headstock. Now it is curing for 10 days and I will then buff it out. Oh, I used Dr Dux oil and it was really pleasant to work with, smells pretty good and performed well with the U-Beaut, again this was Steve's recommendation for the oil. The guitar looks good right now before buffing, but as Dave mentioned, I need to pay more attention to the final prep. prior to finishing. I noticed some small gaps between the puffing and top in some areas, and right where it joins at the bottom. I guess I could have use the super glue method to fill some of these, although they weren't noticeable until the finish started going on. This is where it would have been better to look it over really closely after the initial wash coat of shellac.

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Kurt Thomas

"There's a first time for everything even if you do it by mistake."

No Oil or Shellac added to the pad with the pumice method. All the binding material that you need is the two or three coats of thin Shellac that have already been applied to the wood.
Put a pinch of pumice on the surface of a pad (that is damp with just alcohol alone). Then add a few more drops of alcohol to the surface of the pad, directly onto the pumice. This 'clears' the pumice and will stop the White deposits showing.
Any more pumice that is added to the pad must always be cleared with alcohol prior to applying it to the wood.

Oil is used when building the Shellac, after the pumice/pores have been filled and after it has fully dried.
There is a method for building Shellac without the use of Oil but it is a different technique.

Oil varnish is not an evaporative finish, so the typical french polishing technique does not apply (OK, some Violin makers may use a cloth or their fingers!). Whether you can apply it directly over shellac depends on the actual Shellac and the actual Varnish. The rule is : the softer stuff goes on top of the harder stuff. . . or lean to fat. A hard finish over a softer finish (over time) tends to produce craquelure, mud cracks.
I have done Oil over Shellac many times but my Oil varnishes are not the modern hard resins. You also need to be mindful of the adhesion properties between the two finishes. As a rule I would stay clear of mixing them (other than initial seal coats), it simplifies matters and generally speaking leads to less problems. Stay with Oil or stay with Shellac.
Visually it is hard to beat an Oil varnish IMO. Not that Shellac is poor. You notice the difference more when doing a side by side test. Individually they can both be very good finishes.
Spritz with water and wet sand to level. Dry sanding and clogged paper sounds like a recipe for some pretty bad scratches.
I do very little levelling with French Polishing, mainly at the end to remove any obvious lines or swirls. With Spirit varnishing (brushing shellac) I level every 6 or 7 coats. With Oil varnishing I remove the obvious nibs and level just before the last one or two coats. I don't believe in removing what you have just put on, unless it is necessary of course. Then again I deliberately avoid the extremely flat, high glossy glass like finish. To my eye it is too cold and hard looking. If you want that type of finish you will need to level sand to a much higher degree. Your woodwork will also need to be very flat prior to putting on any finish.

David,
Thanks for sharing your video and congratulations for the excellent results. I have been working with VJ for the past year trying to develop a spraying technique for RL. We have tried several different solvents and mixture ratio concentrations. Spraying is certainly a different process than FP so I don't want to hijack your thread off course. Long story short I love RL and it has become our standard finish.

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tim...
http://www.mcknightguitars.com

Hi Don ... I use a medium pumice that I colour with powdered tempera paint (Sergei de Jonge's idea ... eliminates any white specs from uncleared fill). I wipe a light coat of thin (1 pound-ish) sellac over the back & sides, then quickly start making a slurry of pumice over the instrument by dipping my filler fad (same as my normal fad, but with courser cloth) into the pumice and rubbing it around the instrument. I makes a mucky mess that I then leave for 30 minutes or so. I then take my filler fad and add some alcohol to the front (toe) of the fad ... leaving the back (heel) dry. This way, if I need some alchohol to loosen and move the slurry, I use the front of the fad ... but if I then need less alcohol, I use the heel. The key is getting the slurry at the exact right "wetness" so that it fills the pore without dragging any of the slurry out of the pores. It's a fine balance, but when you get it right, it completely fills the pores. Keep in mind that pumice doesn't shrink, but shellac of course does ... so the more shellac that's involved (i.e. a heavy or multiple sealer coat ... or adding shellac to the fad along with alcohol) the more sinking you will get. I usually wipe the slurry at around a 45 degree angle, but experiment a bit.

This is of course not the only way to do a pumice fill (or even the "best" way for that matter) ... just the way that I'm currently doing it.

Hey Tim ... I didn't know you were using Royal-Lac ... nice!!!

Yes, I've used it on 9 guitars so far. It has the best clarity and highest gloss of any finish I have tested. Its pretty amazing stuff. I'm not sure what VJ is adding to it but it works well. You can't scratch it with your fingernails, but you can dent the wood under neath which means its abrasion resistant but flexible. I have done a cross hatch peel test and it won't delaminate. I've also tossed samples in my freezer and then brought them up to 100*F (fast) then back to the freezer and no crazing.

Have you had any issues with it sinking into softwood tops?

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tim...
http://www.mcknightguitars.com

How does Royal-Lac handle repairs? Does it "burn in" after it has fully cured?

IME. It will burn in within a short window of 2-3 weeks. After its fully cured (>4 weeks) its best to abrade before making a repair. Adhesion is excellent and on par with shellac.

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tim...
http://www.mcknightguitars.com

Hello, Tim.

Could you give more details on your finishing with the R.L.? Filling, sealing, and the application method for the top coats??

BTW, you are doing some really nice work. I sure miss those Little Brother jams.

James

Good afternoon Tim,

I too would would love to know some details on how you apply Royal Lac? As a basement novice, Nitro and other finishes are a big "no go" due to space and family health considerations.

Currently using Z-poxy and Vermont Natural Coatings.

Thank you,

Ray

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Guitar Building = Continuous Improvement Process

I don't know what Tim's process is, but I'd suggest that you guys watch Robbie O'Brien's video on finishing with Royal Lac. It is available on Vijay's site. It really lays out the variable ways to do it pretty well, although he does not cover spraying. As I see it, the key, with Royal Lac, is getting it on the surface in question. It sands just fine after the suggested drying time, with little gumming up. You don't really even have to wait out the full curing time( a couple of days is enough) to wet sand with MicroMesh and hand polish with Swirl Remover and Show Car Glaze. I did a test and got a pretty good finish in less than a week. Just doing it in gaps of the work day. Application takes minutes. I don't think I'd call it French polish, but just Shellac finish.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I'll start a new thread to answer questions instead of Hi-Jacking David's.

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tim...
http://www.mcknightguitars.com

David, thanks for the comments, I will repeat I am happy with Royal lac and I'm pretty sure it will be my new go to finish.. I use VERY little oil in my normal FP technique so maybe that is in fact my issue.. On the other hand I seem to be able to get good results basically padding on the finish letting it cure a bit and working through grits & compound to as you say a nice glass shine..

I'll have to play around on some scrap.. obviously more than one way to skin a cat here..

Kerry

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My Website http://klw-strings.com
My Luthier's Blog...http://klwstrings.blogspot.com

Hi Kerry ... I agree with your "there's more than one way to skin a cat" philosophy. Sounds like you're getting great results with your method too.

I don't agree with the whole skinning a cat philosophy at all...
...and neither does my cat!

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."